SOFIA (Bulgaria), February 1 (SeeNews) - Bulgarian machine engineering company Hydraulic Elements and Systems (HES) [BUL:4HE] said that it expects its net sales revenue to decrease by an annual 3.8% to 59.8 million levs ($35.1 million/30.6 million euro) in 2019, despite its projections for strong sales in the first quarter of the year.